MoA of agomelatine
Agonist of melatonin MT1 and MT2 receptors (antagonism at 5-HT2c receptors)
MoA of TCAs
Blocks transporters such that monoamines do not undergo reuptake. This allows for more of the monoamines to stay within the synapse.
Adverse effects of MAOIs
postural hypotension (accumulation of dopamine)
restlessness and insomnia (CNS stimulation)
serotonin syndrome
Drug interactions of MAOIs
Cheese effect
tyramine accumulation
serotonin syndrome with serotonin and NA reuptake inhibitors
Symptoms of depression:
Misery, apathy, pessimism Low self esteem Indecisiveness, loss of motivation retardation of thought and action loss of libido Sleep disturbances and loss of appetite
What is the monoamine theory:
Deficits in monoamine neurotransmitters cause depression
- from the observation of reserpine which inhibits NA and serotonin storage
MoA of MAOIs:
Increase biological availability of monoamines
Example of MAOIs:
Phenelzine
Moclobemide
Drug interactions involved with MAOIs
Other drugs enhancing serotoninergic function
Cheeses and concentrated yeast products
Describe Monoamine Theory
Limitations of monoamine theory
Main enzyme which breaks down 5-HT and NA respectively
5-HT: MAO-A
NA: Both MAO-A and MAO-B
What class of drug is Phenelzine under? Describe its MoA and selectivity
AE of MAOIs and their causes
Type of food that interacts with MAOIs and hence limits the use of MAOIs
Concentrated yeast products (e.g. marmite) and cheese (acute hypertension)
Describe the Drug-food interaction with tyramine and MAOI
Why is the tyramine effect less likely to occur with moclobemide compared to Phenelzine
Moclobemide is a reversible MAO-A selective MAOI:
Name three TCAs which are non-selective for SERT/NET
Name a TCA selective for NET
Desipramine
MoA of TCAs
Inhibits 5-HT and NA reuptake transporters (SET and NET)
Benefits of Nortriptyline over the other TCAs
A second generation TCA.
Milder side-effects leading to increased compliance
Three AEs of TCAs
Two reasons why TCA can potentially participate in drug-drug interactions
Why is sedation caused by TCA not a main concern in using it?
Tolerance can be developed in 1-2 weeks